Jermaine Gresham is undergoing arthroscopic knee surgery this afternoon to determine the severity of an injury suffered during last Tuesday's practice according to Oklahoma head coach Bob Stoops.

Three separate MRIs failed to detect why Gresham's knee locked up on him in practice, so Stoops says the arthroscopy will allow doctors to determine whether Gresham will be back this season.

"What the scope will be able to tell us is what is making his knee lock. When it locks it could be some loose body in there that they can remove and he can resume, or sometimes maybe the cartilage needs to be stitched together," explained Stoops. "Until they know that, we won't know."

Stoops said if the doctors find loose material that can be easily removed, Gresham could return to the field in two weeks.

But if there is major cartilage damage, Stoops said the prognosis isn't good for the All-American tight end to return to the field this season.

"If they have to stitch and repair the cartilage then that is a five-month recovery, which would mean he would be out for the season," said Stoops.

Gresham did not play in the Sooners' opening game against BYU and he hasn't practiced since the Tuesday before that contest.

Gresham was thought to be a sure-fire first-round pick in last year's draft, but chose to return to Oklahoma for his senior season, which is now in doubt. But Stoops doesn't believe this injury, even if it is found to be the worst-case scenario, would be career threatening.

"His long-term health would be fine. His ligaments, everything else looked great in his knee," said Stoops. "It would just be stitching cartilage back together."

The Sooners will make up for Gresham's absence in the immediate future by moving Brody Eldridge from offensive center back to his normal position at tight end.